I like Mayock, Daniel Jeremiah, Joel Klatt and Todd McShay. I mightn't always agree with them but it's obvious that they do their homework, watch tape and form their own opinions.
Bucky Brooks also does his homework, but he's just always horribly wrong about everything.
Mel Kiper Jr is a fraud. A snake oil salesman, who passes off other people's opinions as his own, but doesn't even have the work ethic to read past people's top 100 lists. Once it gets to the late 4th round Kiper has absolutely nothing to contribute, while Mayock is still waxing poetic about 7th round draftees. Bill Tobin called it many years ago, but somehow Kiper still maintains some sort of mythical draft authority persona...